1999 radio into a 1991 miata - problems
 

just purchased a 1991 miata with a radio/cassette player - radio plays perfectly but the cassette player does not work -has a security protection and I have the code #- purchased a 1999 radio/cd/cassette player on e-bay - installed it and all the functions work but only on a very low volume and the speakers in the head rest to not play - seems to have "off" tone as well - reinstalled the "old" set -put in security # and plays great - is the security code only in the radio - not the system - if not I can't press the FF and REV at the same time because the "new" radio have rocker nob - any thoughts about what is happening and how to install it - thanks!!